Notes on the distribution and status of Tanousia zrmanjae (Brusina, 1866) (Gastropoda: Truncatelloidea: Hydrobiidae)

Tanousia zrmanjae is probably the last surviving species of Tanousia; fossil species of the genus are known from interglacial deposits in many countries. During a detailed inventory of the Zrmanja River the occurrence of live specimens of T. zrmanjae was confirmed at only two sites in the middle section of the river while empty shells were found at another 10 sites, also in the middle river section, between the Jankovica Buk waterfalls and the Visoki Buk waterfalls near the confluence of the Zrmanja and Krupa rivers. The recent occurrence is probably limited to a few sites and thus T. zrmanjae should still be regarded as critically endangered.